Sprinkling apparatuses are mainly used in the horticultural field for the surface-covering water supply of plants, but can also be used for dampening other surfaces, such as sand tennis courts and the like, which are to be kept moist. A sprinkling apparatus is normally set up in fixed manner, connected to a water supply and produces a sprinkling pattern, which determines the shape and size of the sprinkled surface area, as well as the sprinkling density. It is desirable for a variable use of such sprinkling apparatuses to be able to adjust the sprinkling pattern, in order to adapt the sprinkling apparatus to the intended use.
Such sprinkling apparatuses have a nozzle arrangement with a plurality of nozzles connectable to a liquid supply and in particular a water supply. Each nozzle has a nozzle inlet facing the liquid supply and connected by means of a nozzle duct to a nozzle outlet spaced from the nozzle inlet. A nozzle arrangement is a monodimensional or multidimensional array of nozzles with substantially fixed, predetermined, relative positions. A predeterminable sprinkling area must be dampened, it is appropriate to avoid spray formation with respect to the nozzles, because fine water particles can easily be blown away by the wind. Thus, a nozzle is preferably constructed as a single jet nozzle for delivering a bundled liquid jet.
For adjusting the sprinkling pattern of so-called square sprinklers with a plurality of separate nozzles, it is known either to separate the nozzle inlets from the liquid supply or to seal the nozzle outlets, it being possible for the sealing measures to cover individual nozzles or also nozzle groups.
In a square sprinkler described in German patent 1 926 735, in the interior of a nozzle box is mounted in rotary manner a sleeve with different openings by means of which it is possible to block or free in groupwise manner the nozzle inlets provided on the nozzle box. The arrangement of a sealing mechanism in the interior of the nozzle box is constructionally complicated. Only a limited number of different sprinkling patterns can be set and are predetermined by the distribution of the openings in the sleeve.
In a square sprinkler known from European patent 713 426, the interior of a nozzle box is provided with an arrangement with camshaft and tilting levers in each case associated with the nozzles. By means of the camshaft the tilting levers are moved in such a way that individual nozzle inlets are blocked/sealed or freed. Here again, an adjustment is only possible within the scope of the predetermined camshaft design. The blocking mechanism is complicated and correspondingly fault-prone.
In the square sprinkler described in DE 31 19 094, a slider is displaceable in the longitudinal direction of the nozzle box in the interior thereof, so that the nozzles can be successively shut down from one side. The adjustment possibilities of this square sprinkler are very limited.
In the square sprinkler known from U.S. Pat. No. 3,423,024, individual nozzles can be shut down by covering the nozzle outlets. Covering is brought about by annular covering elements, which are snapped onto the outside of the tubular nozzle box and, when necessary, are shoved over the particular nozzle outlet to be closed. Particularly in the case of lime-containing water, sealing problems can arise in this square sprinkler which impair the adjustability of the sprinkling pattern.
The problem of the invention is to obviate the disadvantages of the prior art. In particular, a permanently operationally reliable sprinkling apparatus is to be provided permitting a variable setting of the sprinkling pattern.